0

I'm not sure if x264/5 use CPU and if h264/5 use GPU and also if h265 is basically HEVC_NVENC for NVIDIA GPU acceleration. So, if you could give me more info about these encoding types it would be great. I understood that, summing up a lot, x26* use CPU and are slower but more accurate while h26* are the opposite but h265 is the most recent and optimal trade off. Furthermore, I was trying to convert a video using GPU acceleration and my question is:

Does the following command tell to the GPU to use h265 to encode a video holding the same audio and at upgrading it at its maximum video quality? Furthermore, are there other ways to express the same command?

ffmpeg.exe -hwaccel_output_format cuda -i "input" -c:v hevc_nvenc -preset medium -rc constqp -qp 0 -c:a copy "output"
Fab98
  • 1
  • 1
  • 3

1 Answers1

2

H.264 and H.265 are video codecs for compressing image frames to video.

H.264 is a very widely supported standard that's been around a long time. It provides good efficiency. H.265 is a newer codec which can reduce your bandwidth requirements for a given quality by around a quarter to a third, for most videos. (Or, you can increase quality for the same bandwidth.) H.265 is a patent-encrusted cluster (even more than H.264), and there are currently three groups who claim you must license with them to use it.

I'm not sure if x264/5 use CPU and if h264/5 use GPU

x264 and x265 are open source encoder implementations of the H.264 and H.265 codecs. They run on the CPU.

and also if h265 is basically HEVC_NVENC for NVIDIA GPU acceleration

Yes, that's basically correct. GPUs with NVENC support can encode H.265 video.

Does the following command tell to the GPU to use h265 to encode a video holding the same audio and at upgrading it at its maximum video quality?...

No. Maximum quality would actually be lossless encoding, which is apparently supported.

Brad
  • 159,648
  • 54
  • 349
  • 530